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LEAF AND FLEA BEETLES

CHRYSOMELIDAE: GALERUCINAE

T

he Galerucinae, including the jumping flea

beetles (tribe Alticini), includes more than

15,000 named species, making it one of the largest

beetle subfamilies, accounting for almost half of

the diversity of the enormous leaf beetle family

(Chrysomelidae).

Almost all galerucines feed on living plants, the

adults eating the leaves and the larvae roots or

stems. Many species are pests of agriculture or

horticulture, while others are important as

biocontrol agents of invasive weeds. Some genera,

such as the widespread Longitarsus and the New

World Diabrotica, include hundreds of species, and

accurate identification can be challenging and

involve dissection of adults. This diversity is driven

by host-specificity; the majority of galerucines are

associated with only a single genus or species of

plant, and have evolved very closely with their

hosts, so they are able to metabolize toxic anti-

herbivory chemicals the plants produce in defense.

A few genera feed on mosses or even general

detritus; these include some of the smallest flea

beetles at only 1 mm long, and new species are

still being discovered in the leaf litter of

forest floors worldwide. Another recent

discovery, which breaks new ground in

leaf beetle behavior and adaptation,

is the amazing genus Myrmeconycha,

named in 2017; the four South and

Central American species are

myrmecophilous, meaning they live

with colonies of ants, a behavior well

documented in some beetle groups but not

in leaf beetles. The largest Galerucinae is

Palaeosastra gracilicornis, which reach 20 mm, from

the montane tropical rainforests of New Guinea.

subfamily

Galerucinae

known species

15,500

distribution

Worldwide, especially in the tropics

habitat

Agricultural fields, plains, temperate and

tropical forests

size

1–20 mm

diet

Adults eat leaves and larvae the stems and

roots of living plants, in almost all cases

flowering plants

notes

The larvae of the African flea beetles of the

genus Diamphidia collect a toxin from their

host plants, called diamphotoxin, and store

it in their bodies. Larvae and pupae are

traditionally collected by the San Bushmen

of the Kalahari Desert, and used to poison

arrowheads for hunting, in the same way that

CHRYSOMELIDAE: GALERUCINAE—Leaf